The article did address this:
The internet loves roasting “boomers,” the shorthand term for the Baby Boomer generation born in the ‘50s and ‘60s. Admittedly, most boomer shooter fans are likely Gen-Xers and Millennials, but they’re still co-opting the term in a sarcastic but positive way that conveys the old-school nature of this niche genre.
It all comes down to it rolling off your tongue better.
I know I know. Just thought it was interesting that they had the same thought process in the article too. 😄